The invention relates to a screw mechanism.
Screw mechanisms of this type, like e.g. ball screw mechanisms, are well suited for implementing rapid adjustment motions under a relatively slight load. However, when a transmission of high static loads is involved, a screw mechanism with rolling bodies is less suitable because the force transmission is realized across very small contact surfaces between rolling body and rolling body groove.
When using a ball screw mechanism in an injection molding machine, there is thus the problem that the screw nut, provided to execute the opening and closing motions of the moving platen in a rapid manner, although being well suited for quick-action movement, has difficulty to withstand the significant loads during application of the clamping force and there is a considerable risk of wear.